cb->buffer[cb->head] = data; cb->head = next_head; return 0;
This is a thoughtful request. The (for dsPIC30/33 and PIC24 families) is now legacy (superseded by XC16), but many engineers still maintain projects on it. mplab c30 compiler
INTERRUPT(_U1RXInterrupt, 6) while (U1STAbits.URXDA) c30_cbuf_put(&uart_rx, U1RXREG); head] = data
void init_uart_buffer(void) c30_cbuf_init(&uart_rx, uart_rx_buf, 64); head = next_head
A for C30 would address its most common real-world pain points: poor RAM banking management , lack of built-in circular buffer support for DSP , and verbose ISR syntax .
// Interrupt-safe get inline int c30_cbuf_get(c30_cbuf_t *cb, unsigned char *data) if (cb->head == cb->tail) return -1; // empty
*data = cb->buffer[cb->tail]; cb->tail = (cb->tail + 1) & cb->mask; return 0;